The invention concerns an apparatus for connecting a wire to a contact element or the like by deformation of clamping or terminal portions of the contact element or the like by means of pressure members, in particular pressure members of a crimping tool which is arranged interchangeably in an impact press and which has a movable crimping punch or plunger which in a crimping position produces the deformation. The invention also concerns a connecting process for contact elements.
Apparatuses of that kind for cable manufacture, for example for fixedly connecting wire ends to plugs and cable shoes or connector lugs, usually comprise an impact press with a vertically movable pressing punch or plunger which acts on a pressure head of the crimping tool which is disposed therebeneath, wherein crimping punches or plungers provided in the crimping tool are moved downwardly and secure a horizontally inserted plug member or the like contact element to the end of a cable or wire, by virtue of the deformation of clamping or terminal lugs. The end of the cable or wire is stripped of its insulation to a certain length so as to provide a diameter which is smaller than the insulated portion. The so-called crimping dimension of the punch edge or edges acting on the wire, being the dimension that is necessary for the described crimping procedure, is adjusted by hand in dependence on the cross-section of the wire and the form of the contact element.
An apparatus of the kind set forth above having a shaping punch or plunger or crimper member, by means of which sheet metal lugs are connected to a cable by deformation is described in the present applicants' German laid-open specification (DE-OS) No. 40 39 051. The edges of the sheet metal lugs which are of a U-shape configuration in cross-section are rolled in by the crimper member so as to produce a structure which is approximately heart-shaped, also in cross-section.
It is often necessary for a plurality of inwardly directed radial deformation portions to be produced in sleeve-like or tubular contacts, for which purpose for example star-like wheels on a lever arm are known, the wheels rotating about an axis, with a plurality of impact surfaces. Such apparatuses are provided with their own drive and are overall of an individual configuration, that is to say they are designed specifically for a respective contact and are therefore expensive.
In consideration of that state of the art, the inventor set himself the aim of designing an apparatus of the kind set forth in the opening part of this specification for producing a plurality of inwardly directed deformation portions in a sleeve-like contact element and in the form of a quick-change tool for impact presses. The latter can then be used as a flexible basic piece of equipment.
That object is attained by the teaching of the independent claims; the appendant claims set forth advantageous developments.
To produce a plurality of deformation regions on the contact element, a number of crimping punches or plungers, said number corresponding to the number of deformation regions to be produced, is arranged around a receiving opening, which crimping punches can be moved by pressure jaws or the like members into the crimping position, wherein the pressure jaws or the like members are in turn movable by pressure punches or plungers which are provided at an angle with respect thereto.
For that purpose, it has proven to be desirable to arrange on both sides of a straight line of symmetry, pressure punches, which are substantially parallel thereto, of the crimping tool, which punches engage into the path of movement of inclined surfaces of the pressure jaws, by means of surfaces which are inclined at an angle relative to the axis of symmetry.
In accordance with the invention, for the purposes of return movement of the pressure jaw, disposed in opposite relationship to the inclined surface or surfaces thereof is a respective parallel inclined surface which is associated with a second inclined surface of said pressure punch. The co-operating return surfaces of the pressure jaws and the pressure punches extend inclinedly relative to the axis of symmetry, in order to restore the initial position.
In accordance with a further feature of the invention the pressure jaw has a taper surface which crosses the axis of the associated crimping punch and can be pressed against a punch surface which is parallel thereto. In accordance with the invention the crimping punch is returned from the crimping position by a force-storage means, in particular a compression spring.
It has also been found desirable for the axis of the crimping punch to be disposed approximately at a right angle relative to the taper surface and/or for the crimping punch to be arranged to be movable against the force of a force-storage means into the crimping position.
Advantageously, both the taper surface and also an oppositely inclined oblique groove are formed in a parallelepipedic block of material, wherein the inclined groove affords the inclined surfaces for the crimping and return movement.
In accordance with another feature of the invention, engaging into the inclined groove in the pressure jaw is a rib which projects from the pressure punch in a bar-like configuration and which has said inclined surfaces. Those pressure punches which are connected to a rotary head that can be raised and lowered can also be produced in a simple manner by a cutting machining operation from a block of material.
The pressure jaw is guided towards the crimping punch against the force of a force-storage means which--preferably in the form of a coil spring--embraces a securing pin which is connected to the pressure jaw and which passes through a fixed guide.
The above-mentioned guide for the securing pin is a bore in a part of a housing in which slide tracks for the pressure jaws extend. Thrust tracks for the pressure punches are directed transversely to said slide tracks.
It is in accordance with the invention for an interchangeable crimping insert to be arranged between the thrust tracks and for the crimping insert to be provided with guides for the crimping punches. Those guides are disposed radially relative to the receiving opening in the crimping insert.
In accordance with the invention, by means of a tool of such a configuration, the force of the press is distributed to the pressure punches or plungers of the crimping tool and each force portion of the crimping punch is converted into at least a force which is at an angle relative thereto; that force acts on the crimping punch.